Known in the art are close structural analogs such as 2,3,5,6-tetrahydro-6-phenyl-7-phenacylimidazo-[2,1-b]-thiazolium bromide (cf. USSR Inventor's Certificate No. 910636) and L-(-)-2,3,5,6-tetrahydro-6-phenylimidazo-[2,1-b]-thiazole hydrochloride (levamizole)/Levamizole as Immunomodulator (Chemistry, Pharmacology, Mechanism of Action and Clinical Applications), Dr Alaiosh Par, Chemical Works Gedeon Richter A.G. Budapest, Hungary) mainfesting a stimulating effect in respect of various immunological responses.
This prior art preparation Levamizole, though possessing a broad spectrum of action on the immune system, is toxic and has diverse side effects.